

const pi = Math.PI;
//类
class Circle{
  constructor(radius){
    this.#r = radius;
  }
  get diameter(){
    return 2 * this.#r;
  }
  get circumference(){
    return 2* pi * this.#r;
  }
  get area(){
    return pi * this.#r * this.#r;
  }
  #r = 0;
}
module.exports = Circle;
console.log(module);


console.log('hello','world');
